So why still no EFC mode for EM5?

Have there been any revelations to date as to why Oly have not released a firmware update for the EM5 to give an Antishock 0 mode ?

I've just done a quick search here, and initially when the EM1 got it, people were wondering if it could also be done for the EM5. However the former uses a different sensor, different shutter assembly etc, so nobody was sure if it was possible.

Subsequently however, the EM10 got the update, and its a very strong possibility that this camera DOES have the same sensor and shutter mechanism as the 5.

So is there any update? rumour of it coming? reason why it can't be done?